Portland cement

USING WASTEPAPER SLUDGE ASH (WSA) AS A MATERIAL FOR SOIL STRENGTHENING FOR THE CONSTRUCTION OF LAYERS OF PAVEMENT

The article considers the possibility of using wastepaper sludge ash (WSA) as a soil reinforcement material for the construction of layers of road wear. Loamy sand, sandy loam, silty clay loam, silty clay were chosen as soils for strengthening. The maximum density of the soil skeleton at optimum humidity was established by the method of Proctor. Wastepaper sludge ash and Portland cement grade 400 were used separately for soil strengthening.

Peculiarities of Nanomodified Portland Systems Structure Formation

Regulation of hydration processes on nanostructure scale due to the competition adsorption modifying of hydration products by polycarboxylate and adding of nanosized C-S-H nuclei allows promoting homogeneous distribution of solid phase in the structure of cement paste on the micro- and nanolevel, provides the growth of contact amount between hydrates, results rapid structure formation and strength synthesis of Portland cement system.

POZZOLANIC ADDITIVES FOR PORTLAND CEMENT FOR TRANSPORTATION CONSTRUCTION

Production of Portland cement is one of the most energy intensive among building materials, it is accompanied by significant CO2 emissions: 0,7 to 1 ton per 1 ton of cement, depending on manufacturing technology. Therefore, replacement of Portland cement clinker with active mineral additives of natural or synthetic origin is environmentally and economically viable, while not causing significant adverse changes in the properties of cement binders.

Вплив технологічних факторів на властивості волокнистоцементних виробів

The influence of technological factors on the properties of fibre cement articles is investigated. The research reveals an interconnection between microstructure and strength of the cement matrix with the average density, moisture deformation and warping of fibre cement sheets.

Influence of Fine-Grinded Glass Additives on the Induction and Post-induction Periods of Portland Cement Hardening

The investigation results of changes in cement grout observed during the induction and post-induction periods of hardening while adding fine-grinded glass additives are presented. It is assumed that glass introduction decreases pH of the system due to the chemical interaction with alkaline medium of the cement grout. The obtained results are important for the solving of the problem of glass wastes usage in the cement technology.

Effect of Synthetic Nanodispersed Silica on the Properties of Portland Cement Based Mortars

The work deals with the modification of mortars by small quantities of nanodispersed material. The effect of amorphous nanosilica on Portland cement hydration and hardening has been investigated. The amorphous nanosilica is compared with the known mineral additive – microsilica.

Alkaline Factor in Cements with Glass Powder

The effect of alkaline component in glass powder on the total alkaline content of cement-glass mixtures, which is limited by standards, has been investigated by means of pH-metry? Titration and different extragents. Using experimental and calculated results concerning alkaline activity of glass powder it is possible to develop chemical structure of the cement composites which would meet the standards in regard to total alkaline content.